The invention relates to the technical field of “Intelligent Transportation Systems” (ITS). In particular, the invention relates to the efficient implementation of intelligent transportation systems of this type.
Communication protocols and cooperative safety applications are currently standardized within various initiatives relating to “Intelligent Transportation Systems” (ITS), among others in the European standardization bodies ETSI and CEN, and in the USA in ISO, SAE and IEEE. The aim is to enable cooperative and, wherever possible, accident-free driving for all vehicle manufacturers in the future. The cooperative safety applications also contain, inter alia, collision avoidance applications and collision mitigation applications for side-impact and rear-end collisions. The safety applications addressed and the associated transmission protocols and data formats are documented, inter alia, in the ETSI standard TS 102 637 and in the SAE standard SAE J2735. A Cooperative Awareness Message (CAM) is thus defined in the TS 102 637-2 standard. This message is transmitted at periodic intervals by an ITS station (e.g. by a vehicle) in order to provide other ITS stations (e.g. other vehicles) in the vicinity with selected information (e.g. speed, acceleration and/or position) of the transmitting ITS station. The information exchanged between the ITS stations, e.g. using CAM messages, can be used in the respective ITS stations to recognize collision risks and, where necessary, instigate suitable countermeasures (e.g. warnings).
Along with the reduction of collision risks, the intelligent transportation system ITS can also be used to provide value-added services. Examples of such value-added services are the recording and billing of toll charges, the updating of road topology data (e.g. for navigation systems), the updating of ITS certificates, etc.
The present document concerns, in particular, the technical task of an efficient provision of value-added services of this type by way of an intelligent transportation system ITS. The intention is to ensure that the safety-related functions of the intelligent transportation system ITS (i.e., in particular, the collision avoidance functions and collision mitigation functions) are not adversely affected by the provision of the value-added services.
According to one aspect, a control unit (e.g. a vehicle cooperation control unit) for a vehicle (e.g. for an automobile, a truck and/or for a motorcycle) is described. The control unit can be configured to enable V2X (vehicle-to-X) applications (also referred to as vehicle cooperation applications), wherein the X stands, for example, for another vehicle or for road infrastructure. V2X applications can also be referred to as vehicle-to-X applications.
The control unit can be configured to receive and/or transmit one or more safety-related vehicle cooperation messages via a physical channel of a communication unit of the vehicle. In particular, the control unit can be configured to administer or provide a logical control channel for receiving and/or transmitting one or more safety-related vehicle cooperation messages.
The physical channel may be a wireless transmission channel (e.g. in the 5-6 GHz range). The communication unit of the vehicle typically comprises only one physical channel for transmitting vehicle cooperation messages. In particular, the vehicle may comprise only one single physical channel for transmitting vehicle cooperation messages.
The one or more safety-related vehicle cooperation messages may include one or more “Cooperative Awareness Message” (CAM messages) of the vehicle-to-X network, one or more “Decentralized Environmental Notification Message” (DENM messages) of the vehicle-to-X network, and/or one or more “Basic Safety Message” (BSM messages).
The control unit can be configured to determine an indicator that the vehicle (also referred to as the ego vehicle) has a reduced risk of conflict with another road user (e.g. with another road user of the vehicle-to-X network) in a first time period. In particular, one or more indicators can be determined for the existence of a reduced risk of conflict with all (ITS-enabled) road users in the reception/transmission range of the ego vehicle. The control unit can be configured to determine one or more of the following indicators: an indicator of the stopping of the ego vehicle in the first time period; an indicator of the stopping of another vehicle in front and/or behind the ego vehicle in the first time period; an indicator that the ego vehicle is located in a traffic jam in the first time period; an indicator that the ego vehicle is located in front of a red traffic light in the first time period; an indicator that the ego vehicle is located in a non-public area (e.g. on a parking lot or at a filling station) in the first time period; and/or an indicator that the ego vehicle is located on a road section on which no oncoming traffic, no crossing traffic and/or no traffic merging onto the road is to be expected (e.g. on a highway or expressway). The above-mentioned indicators may represent indications that a reduced risk of conflict exists. If a plurality of the above-mentioned indicators exist, the risk of conflict can be reduced and, if possible, also entirely excluded. This means that the control unit can be configured to determine a multiplicity of indicators of the existence of a reduced risk of conflict and/or to determine a probability of a risk of conflict therefrom. A suitable combination of indicators (e.g. in specific scenarios) can produce a probability of (almost) zero.
The control unit can be configured to receive sensor data from one or more sensors of the vehicle. The sensors may, for example, be a camera, a radar, an ultrasound sensor, a GPS receiver, etc. The control unit can be configured to determine the indicator(s) of the existence of a reduced risk of conflict (also) on the basis of the received sensor data. In addition, received vehicle cooperation messages can be used to determine the one or more indicators.
The control unit can furthermore be configured to receive and/or transmit a non-safety-related vehicle cooperation message via the physical channel of the communication unit in the first time period. In particular, the control unit can be configured to administer or provide a logical control channel for receiving and/or transmitting one or more safety-related vehicle cooperation messages. The control unit is typically configured in such a way that the physical channel of the communication unit is assigned either to the logical control channel for receiving and/or transmitting one or more safety-related vehicle cooperation messages, or to the logical service channel for receiving and/or transmitting one or more non-safety-related vehicle cooperation messages (in a mutually exclusive manner). In the first time period, the physical channel of the communication unit can be assigned at least partially to the logical service channel due to the reduced risk of conflict.
In particular, the control unit can be configured to determine a probability of a risk of conflict in the first time period (on the basis of one or more indicators for the existence of a reduced risk of conflict). Furthermore, the control unit can be configured to assign the physical channel of the communication unit at least partially to the logical service channel in the first time period if the determined probability lies below a predefined probability threshold value.
The control unit can thus be configured to use the same physical channel for transmitting safety-related vehicle cooperation messages and for transmitting non-safety-related vehicle cooperation messages and to increase the safety risk to a controlled extent only (if at all). This enables a low-cost provision of value-added services (through the transmission of non-safety-related vehicle cooperation messages) in vehicle-to-X networks.
The control unit can be configured to predict a reception time period for receiving a periodic safety-related vehicle cooperation message of another ITS station (e.g. of an emergency vehicle). It can furthermore be determined that the predicted reception time period occurs in the first time period. The control unit can be configured to assign the physical channel of the communication unit to the logical control channel in the predicted reception time period in order to ensure that the periodic safety-related vehicle cooperation message of the other ITS station can be received. Furthermore, the control unit can be configured to assign the physical channel of the communication unit to the logical service channel before and/or after the reception time period (insofar as these time periods still occur in the first time period).
The control unit can be configured to transmit safety-related vehicle cooperation messages (e.g. CAM messages) via the physical channel of the communication unit. The frequency of the periodic safety-related vehicle cooperation messages may be variable. The control unit can be configured to reduce the frequency of the periodic safety-related vehicle cooperation messages in the first time period (in comparison with the frequency before and/or after the first time period). The time periods within the first time period for transmitting non-safety related vehicle cooperation messages can thereby be increased.
According to a further aspect, a method is described for transmitting vehicle cooperation messages. The method comprises the receiving and/or transmitting of at least one safety-related vehicle cooperation message via a physical channel of a communication unit of a vehicle. The method furthermore comprises the determining of at least one indicator that the vehicle has a reduced risk of conflict with at least one other road user in a first time period. If at least one indicator has been determined, at least one non-safety-related vehicle cooperation message can be received and/or transmitted via the physical channel of the communication unit of the vehicle in the first time period.
According to a further aspect, a software (SW) program is described. The SW program can be configured to be executed on a processor and as a result to carry out the method described in this document.
According to a further aspect, a storage medium is described. The storage medium may include an SW program which is configured to be executed on a processor and as a result to carry out the method described in this document.
It should be noted that the methods, devices and systems described in this document can be used both alone and also in combination with other methods, devices and systems described in this document. Furthermore, all aspects of the methods, devices and systems described in this document can be combined with one another in a variety of ways. In particular, the features of the claims can be combined with one another in a variety of ways. Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.